Method of heat-setting twisted polycarbonamide yarn

ABSTRACT

The improved method of this invention omits autoclaving and substitutes tumbling of the yarn as skeins at a selected temperature between 120* and 240*F. for a period of 2 to 10 minutes in the heat-setting of twisted polycarbonamide yarn. The process gives a product carpet with locked tuft tips.

United States Patent 1191 Gomez et al.

METHOD OF HEAT-SETTING TWISTED POLYCARBONAMIDE YARN Inventors: Climaco Alberto Gomez, Colonial Heights; Marvin Dennis Lewis, Richmond; lan Charles Twilley, Chester, all of Va.

Assignee: Allied Chemical Corporation, New

York, NY.

Filed: Dec. 3, 1973 Appl. No.: 421,207

References Cited UNITED STATES PATENTS 2,019,185 10/1935 Kagi 57/140R Mar. 25, 1975 Bouhuys 57/l57 TS Hood 57/157 TS Sommaripa 57/ 140 R Schneider et al. 57/140 R Kline et al 28/72 R Yoo 57/l64 Wood, Jr, et al. 57/l57 TS Primary Examiner-John Petrakes ABSTRACT The improved method of this invention omits autoclaving and substitutes tumbling of the yarn as skeins at a selected temperature between 120 and 240F. for a period of 2 to 10 minutes in the heat-setting of twisted polycarbonamide yarn. The process gives a product carpet with locked tuft tips.

5 Claims, No Drawings OF HEAT-SETTING TWISTED POLYCAR'BONAMIDE YARN Process floor space Since the autoclavir'ijg structures IS reduce heat set in this manner when tufted into a fabric such 'as a carpet and subsequently dyed with hot, wet agitation has excellent twist retention and entangled locked tuft tips when the tufts have been cut. The yarn made BACKGROUND OF THE INVENTION 5 by the process of this invention also has greater bulk,

ozone resistance, wear resistance and is more economii cal to produce. The excellent twist retention is uniform Thls. mventlon relates an lmproved method to heat along the entirelength of each tuft. The amount of agiset twisted polycarbonamide yarn.

Twisted and heat Set 0] carbonamide (n Ion) tation during tumbling is not critical and can be varied p y y by the speed of agitation of the tumbler and by the bulked continuous filament yarn IS extensively used in amount of yarn agitated per tumbler load. The followcut pile and frieze style carpets and other fabrics. The

rior an method of roducin this am from bulked mg tables contrast the prior art with the method of this p p y invention and set forth the advantages over the prior continuous filament yarn consisted of twisting, skeming, tumbling and autoclaving followed by drying if necessary conditioning and backwinding from skeins TABLE I onto a carrier to form a package of yarn. Autoclaving P I A M th d X was considered essential in the prior art since it'was ben e 0 lieved that autoclaving the twisted yarn in high pressure .Twi sti ng Twisting steam for relatively long periods set the twist in the skemltlg skemkng Tumbling Tumbling yarn structure. It IS known m.U.S. Pat. No. 2,695,509 iAumclaving to heat set twist in yarn by running a single end of yarn lDryilrlg (optional) C r 00 mg 00 mg through a heating chamber, however, this yarn is not Backwinding Backwinding tumbled and not skeined. 1

TABLE II 1. Greater Bulk The bulk of'tumbled only yarn is greater than tumbled and autoclaved yarn. The linear density of tumbled only yarn is less than autoclaved yarn. Autoclavin kills" bulk and raises linear density. Yarn made y the process 0 this invention produces carpets with greater bulk than comparable carpets produced with an equal amount of prior art yarn.

2. Better Twist Because of higher residual yarn and crimp shrinkage of tumbled yarn, these Retention shrinka es in ot wet processing (dyeing) result-in filament entanglements that loc the twist of the structure at the tip end of the cut tuft. Autoclaved yarns are not locked nearly as well and therefore .have a tendency to untwist.

3. Better Walk-out Because of the locked tips with tumbled only yarn, the twisted structure Performance is much more stable upon floor wear. The autoclaved tips are unstable and the individual yarn com onents of the twisted structure separate resulting in flared or burste tufts which is most undesirable.

4. Improved Since lower temperatures and shorter exposure times are used for tumbled Atmospheric only yarn, the ozone resistance of the tumbled only dyed yarn is much Gas Fading and greater than for autoclaved dyed yarns. Dyeing uniformity is also improved. Dyeing Uniformity 5. More Economical is eliminated, the cost of throwin twisted step because of less labor, less capital, and ess SUMMARY OF THE INVENTION The method of this invention omits autoclaving. The

yarn is simply twisted, skeined and tumbled as skeins at a selected yarn temperature of between 100 and 240F. preferably between 120 and 200F. and even,

preferably 6to 8 minutes. It has been found that no autoclaving is necessary when these conditions are used. The selected temperature during tumbling should be controlled to within i 15F. The yarn is then conditioned as skeins and backwound into a package of yarn. By conditioned is meant the yarn is cooled and/or dried or allowed to cool and/or dry at ambient conditions. Any of the polycarbonamide yarns can be used such as polycaprolactam (nylon 6) or polyhexamethylene adipamide (nylon 6,6). The heating medium can be either steam or hot air. Surprisingly, yarn which is twisted and DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLE I A. A bright, amine terminated, bulked continuous filament polycaprolactam (nylon 6) 1,300 denier filament yarn was twisted in a conventional manner to 3 turns per inch Z by 3 turns per inch S, skeined, and tumbled in steam at the yarn temperature. given in the following tables. This acid dyeable yarn was then dried, if necessary, conditioned and the skeins were backwound into a conventional yarn package. The tumbling was carried out in a No. l-Iubsch Commercial Dryer for about 7 minutes. i

B. An identical yarn except for being produced from ,acid terminated polymer was processed in the same manner.

C. Yarns identical to those above were processed using hot air as the heating medium instead of steam.

3 EXAMPLE n Method of Setting Twist in Control, Prior Art Yarn A. Autoclaved The yarn of Example IA was processed by the prior art method by twisting to 3 tpi Z by 3 tpi S, skeining, tumbling with live steam at a yarn temperature of 140F. for about 7 minutes, autoclaving for approximately 60 minutes at the cycle of vacuum and temperature conditions standard in the industry (maximum steam temperature during the cycle of 280F.) conditioning to room temperature and backwinding into a conventional yarn package.

B. Autoclaved The yarn of Example [8 was processed as above.

C. Single End Treatment The yarn described in Example IA and IB was processed as follows. A Relset 20 position machine with a 50 foot coil was run at'250 yards per minute to heat each end of yarn with hot air at 230C. using a 170C. band heater. The pressure was 30 psi in and 2-3 psi out. The band heater is located above the coils to heat them. The air is heated to temperature in the air storage tank with electrical resistance heaters or other heating means.

TABLE III Carpet Tuft Tip Coherency Yarn Yarn from Temperature After Wear Example in Tumbling Before Wear and Cleaning IA I4()F. 16.6 2l.0 IB l40F. 16.9 33.7 IIA 55 I20* IIS 5.2 l8.7*

Increase in force due to entanglements below the tip in spite ol'exeessire opening at the tip. tip flare was notieeahle.

DESCRIPTION OF TIP COHERENCY TEST Purpose:

The tip coherency test measures the degree of filament bonding of shag carpet tufts at their tips. Principle:

This test measures the force in grams required to separate the tip of a shag carpet tuft composed of two yarns twisted together.

Procedure:

l. Cut a tuft from thecarpet.

2. Separate the yarns at the base of the tuft and continue the separation up to about one-fourth inch from the tip.

3. Grip the two yarn ends in an Instron Tensile Tester.

4. Start the lnstron with a cross-head speed of inches per minute.

5. Record the force in grams required to completely separate the two twisted yarns.

6. Test a representative number of tufts and report Tip Coherency as the average force required. Table Illa shows visual appearance before and after wear. Results show carpet in low weight carpet made of yarn of this invention is superior after wear.

TABLE. Illa Visual Appearance Before And After Wear 10.000 Treads) High Weight Carpet Low Weight Carpet Yarn processed on the Relset machines has about the same bulk as IA.

Bulk Measurement Purpose:

To measure the volume occupied by a known mass of yarn. Principle:

This test measures the volume in ml. occupied by 1 gram of yarn in a 1 inch diameter tube under a stress of I50 gm/in Procedure:

1. Weigh out exactly one gram of yarn. The yarn may be from packages, skeins, or carpets.

2. Cut the yarns into three-fourth inch lengths and allow to fall into a ml. graduated cylinder (1 inch inside diameter).

3. Place a 1 inch drill rod weighing 118 grams (I50 gm/in into the cylinder and allow to compress the yarn for 30 seconds.

4. Read the volume in 'ml. of the 1 gram of yarn. Significance:

Results obtained with above bulk measurement test have been correlated with a bulk measurement in carpets as shown in Table IV.

TABLE V Carpet Appearance Evaluation Yarn Yarn from Temperature 02 yarn per Tip Example In Tumbling Sq/Yd Carpet Bulk Flare Hand Resilience Hariness 11A & B 24 B" C+ C+ C+ C+ IA & B 165F. 24 A B+ C+ C+ C 1A & B 185F. 24 A B+ C+ C+ C 11C 24 A B+ C+ C+ C IC 150F. 24 A B+ C+ C+ C 1A & B 165F. 21.5 8+ 8+ C+ C+ C IA & B 185F. 21.5 13+ 13+ C+ C+ C 11C 21.5 8+ 3+ C+ C+ C IC 150F. 21.5 B+ B+ C+ C+ C IA & B 165F. 19 C+ B+ C+ C+ C IA & B 185F. 19 C+ 13+ C+ C+ C Carpets were tufted end and end (with acid terminated yarn and amine tenninated yarn in alternating rows) and evaluated visually according to the following grading s stem:

A Exce lent B Good The method of testing for ozone fading is similar to 20 the AATCC Test 129-1968 set forth on page 334/15 of The Journal of American Association of Textile Chemists and Colorisrs, July 30, 1969, Volume 1, No. 16, in an article entitled, A New Test Method for Ozone Fading at High Humidity," by Victor S. Salvin.

The method and the means of measuring the loss of dye consists in dyeing the yarn with a selected dye or dyes, exposing it to ozone at a concentration of parts per hundred million in a test chamber 104F. and 90% relative humidity together with a control nylon sample which was dyed an avocado shade. The control sample is examined periodically until the resulting color corresponds to that of the Standard of Fading (one cycle). It has been found that one cycle is completed when the internal standard has faded sufficiently to give a AE of 2.8, compared to the unexposed standard.

AB is a measure of the change of color between two samples, a smaller AE being a closer match, or less fading of one sample compared to the second sample.

This color difference, AE, was measured with a Hunterlab Color Difference Meter. This instrument meas- C Average D Poor ures color as seen in average daylight in a manner similar to the way in which the human eye responds to the stimulus of color. Experimentation has shown that the eye can match any color with a combination of three primary colored lights, and therefore, that any color 25 can be specified by a three dimensional identification.

The Color Difference Meter measures the light reflected by a specimen through filters that correspond to the three primary lights. These measurements made correspond to the way the average human eye responds to light.

A E. V (AL) (Aa) (Ab) where AL is L -L A0 is a -a 35 Ab is b b and L, a, and b are readings on the Hunterlab Color Difference Meter. L is a to 0 reading of white to black; a indicates redness when positive, gray when zero, and green when negative; b indicates yellow when positive, gray when zero and blue when negative.

TABLE V1 Ozone Fading Exposure to 0;,

Yarn from 6 Hours 12 Hours 18 Hours Yarn Tumbling Example AL AE AL L A Temperature Dyed IA 1.6 2.1 3.1 4.0 4.9 6.3 100F. Disperse Olive'll IA 1.2 1.7 2.5 3.6 3.3 4.8 F. Disperse Olive 11 IA .9 1.4 2.4 3.6 3.3 4.7 F. Disperse Olive 11 IA .6 1.3 3.0 4.1 4.4 5.9 F. Disperse Olive 11 IA .9 1.4 2.8 3.8 4.0 5.4 F. Disperse Olive 11 1B .6 1.3 1.4 2.3 2.6 3.9 100F. Disperse Olive 11 113 1.1 1.6 2.0 3.0 2.9 4.3 120F. Disperse Olive 11 18 1.4 1.9 2.1 3.0 3.0 4.1 140F. Disperse Olive 11 1B .4 1.0 1.6 2.6 3.4 4.0 170F. Disperse Olive 11 1B .7 1.4 1.6 2.8 3.0 4.5 190F. Disperse Olive 11 11A 1.7 2.2 3.6 5.2 5.2 7.1 Disperse Olive 11 11A .2 .6 1.5 1.9 2.0 2.5 Acid Moss Green 1113 1.1 1.8 4.1 6.1 5.9 8.5 Disperse Olive 11 11B 1.4 2.0 3.5 5.7 5.5 9.2 Acid Moss Green IA .8 1.1 1.6 2.1 1.1 2.1 100F. Acid Moss Green 1A .7 .9 1.5 1.9 1.8 2.5 120F. Acid Moss Green 1A .9 1.2 1.3 1.8 2.0 2.8 140F. Acid Moss Green IA .9 1.1 .5 1.3 1.5 2.3 170F. Acid Moss Green 1A .4 .6 .9 1.3 1.5 2.2 190F. Acid Moss Green 113 .9 1.3 2.3 3.4 2.6 4.1 100F. Acid Moss Green 113. 1.6 2.0 2.4 3.5 2.6 4.2 120F. Acid Moss Green IE 1.2 1.6 2.1 2.9 3.1 4.7 140F. Acid Moss Green 18 1.0 1.4 2.1 3.1 3.1 4.7 170F. Acid Moss Green 113 1.4 1.8 2.1 3.3v 3.5 5.3 190F. Acid Moss Green 7 The formulation of the moss green dyebath is given on page -7 of allowed U.S. Ser.No. 223,772, filed Feb. 4, 1973, hereby incorporated by reference.

The formulation of the Olive ll dyebath is as follows: 0.082% Latyl Cerise Y (DuPont) 0.44% Celliton Yellow GA (C. I. 11855) 0.143% Celanthrene Blue CR (DuPont) 2% trisodium phosphate 0.5% Triton X-lOO (ethoxylated nonylphenol) We claim: 1. The method of heat-setting twisted polycarbonamide continuous filament carpet yarn comprising twisting the yarn, then skeining the yarn, then tumbling said yarn as skeins at ,a selected yarn temperature of between about 100 and 240F. for about 2 to 30 minutes, said selected temperature being controlled to within i F., then conditioning said skeins of said yarn, then backwinding said yarn, then tufting said yarn into a fabric, then dyeing said fabric with hot, wet agitation, said yarn in said fabric having excellent twist retention and entangled, locked tuft tips when said tufts have been cut.

2. The method of heat-setting twisted polycaprolactam continuous filament carpet yarn comprising twisting said yarn, then skeining said yarn, then tumbling said yarn as skeins at a selected yarn temperature of between about to 200F. for about 2 to 10 minutes, said selected temperature being controlled to within 1*: l5F., then conditioning said skeins of said yarn, then backwinding said yarn, then tufting said yarn into a fabric, then dyeing said fabric with hot, wet agitation, said yarn in said fabric having excellent twist retention and entangled, locked tuft tips when said tufts have been cut, greater bulk, ozone resistance, and wear resistance.

3. The method of claim 2 wherein said tumbling temperature is selected from a range of from about to 200F. for about 6 to about 8 minutes.

4. The method of claim 2 wherein the heating medium for the tumbling step is steam.

5. The method of claim 2 wherein the heating medium for the tumbling step is hot air. 

1. THE METHOD OF HEAT-SETTING TWISTED POLYCARBONAMIDE CONTINUOUS FILAMENT CARPET YARN COMPRISING TWISTING THE YARN, THEN SKEINING THE YARN, THEN TUMBLING SAID YARN AS SKEINS AT A SELECTED YARN TEMPERATURE OF BETWEEN ABOUT 100* AND 240*F. FOR ABOUT 2 TO 30 MINUTES, SAID SELECTED TEMPERATURE BEING CONTROLLED TO WITHIN = 15*F., THEN CONDITIONING SAID SKEINS OF SAID YARN, THEN BACKWINDING SAID YARN, THEN TUFTING SAID YARN INTO A FABRIC, THEN DYEING SAID FABRIC WITH HOT, WET AGITATION, SAID YARN IN SAID FABRIC HAVING EXCELLENT TWIST RETENTION AND ENTANGLED, LOCKED TUFT TIPS WHEN SAID TUFTS HAVE BEEN CUT.
 2. The method of heat-setting twisted polycaprolactam continuous filament carpet yarn comprising twisting said yarn, then skeining said yarn, then tumbling said yarn as skeins at a selected yarn temperature of between about 120* to 200*F. for about 2 to 10 minutes, said selected temperature being controlled to within + or - 15*F., then conditioning said skeins of said yarn, then backwinding said yarn, then tufting said yarn into a fabric, then dyeing said fabric with hot, wet agitation, said yarn in said fabric having excellent twist retention and entangled, locked tuft tips when said tufts have been cut, greater bulk, ozone resistance, and wear resistance.
 3. The method of claim 2 wherein said tumbling temperature is selected from a range of from about 150* to 200*F. for about 6 to about 8 minutes.
 4. The method of claim 2 wherein the heating medium for the tumbling step is steam.
 5. The method of claim 2 wherein the heating medium for the tumbling step is hot air. 